Mastoiditis-related internal carotid artery thrombosis, a case report

Introduction and importance: Acute internal carotid artery (ICA) thrombosis is a rare complication of mastoiditis, which can spread to intracranial vessels, leading to thrombosis and infarction. Case presentation: An 83-year-old man presented to the neurologist with progressive left-sided ear swelling and peripheral facial palsy lasting several weeks. Intravenous antibiotic was prescribed for chronic mastoiditis. Sudden consciousness disturbance and right hemiplegia occurred during treatment. Brain magnetic resonance imaging revealed acute ICA occlusion with hemispheric cerebral infarction. Surgical intervention for complicated mastoiditis was planned after the acute phase of the cerebral infarction. However, the patient's condition deteriorated due to sepsis, ultimately leading to death. Clinical discussion: Mastoiditis may lead to skull base osteomyelitis, which can directly involve the ICA and cause acute thrombosis. In complicated mastoiditis, early surgical intervention may prevent severe complications. Conclusion: This case highlights mastoiditis as a potential precursor to ICA territory infarction, and delayed aggressive management can result in severe complications.